ECAT Pre General Science Physics MCQ Test With Answer for Full Book

When the bob of simple pendulum is at mean position, its K.E will be

• maximum A
• minimum B
• zero C
• all of them D

If the number of turns of a solenoid (carrying a steady current I) is doubled without changing the length of a solenoid, then magnetic field:

• Becomes Half A
• Becomes double B
• Is not affected C
• Becomes one fourth D
• None of these E

Heating effect of current utilized in:

• Electric motor

  A

• Electric toaster

  B

• Electroplating

  C

• Electric kettle

  D

• Both (B) and (D)

  E

The basic circuit elements of A.C circuit are

• Resistor A
• Inductor B
• Capacitor C
• All the three D

In order to make a voltmeter, high resistance is connected with galvanometer, in

• perpendicular A
• may be paralled or pendicular B
• series C
• none of these D

When the p-n junction is forward biased its resistance is of the order of

• few mega ohms A
• few kilo ohms B
• few ohms C
• few milli ohms D

Which one of the following phenomenon cannot be explained on the bases of Huygen's theory

• Refraction A
• Reflection B
• Diffraction C
• Formation of spectrum D

Balmer series was identified in:

• 1685 A
• 1785 B
• 1885 C
• 1985 D
• 1585 E

Work is a Quantity

• Vector A
• Scalar B
• Non-physical C
• None of these D

A field free region is found:

• Near the outer surface of a hollow charged metal sphere

  A

• In the interior of solid metal uncharged sphere

  B

• In the interior of solid metal charged sphere

  C

• Both (A) and (B)

  D

• Both (A) and (C)

  E

The un-steady streamline flow is called

• laminar flow A
• turbulent flow B
• both of them C
• none of them D

Due to the high value of the input resistance, practically, the value of the current which flows between the input terminals is

• zero A
• small B
• large C
• very large D

During each cycle, alternating voltage reaches a peak value

• One time A
• Two times B
• Four times C
• A number of times depending on the frequency D

Ferromagnetic substances lose their magnetism when heated above a certain temperature, known as

• critical temperature A
• curie temperature B
• high temperature C
• fixed temperature D

The phase at the positive peak is

• Π/2 A
• Π B
• 3Π/2 C
• 2Π D

If a nucleus emits an alpha particle, its mass number decreases by 4 while charge number decreased by

• -4 A
• 4 B
• 2 C
• 1 D

On the exaust stroke, the outlet values opens. The residual gases are expelled and piston moves

• outwards A
• inwards B
• in either way C
• none of these D

Which of the following is an example of a S.H.M?

• motion of a projectile A
• motion of a train along a circular path B
• motion of swing C
• electrons revolving sound the nucleus D

If the value of galvanometer constant k = C/BAN is made small, the galvanometer can be made

• Sensitive A
• Accurate B
• Stable C
• None of these D

The special theory of relativity is based on:

• Four postulates A
• Three postulates B
• Two postulates C
• One postulate D
• None of these E

In a Milikian's oil drop experiment the charge on an oil drop is calculated to be 6.35 x 10^-19C. The number of excess electrons on the drop is

• 3.9 A
• 4 B
• 4.2 C
• 6 D

• 5μF A
• 10μF B
• 3μF C
• 6μF D

The special theory of relativity treats problems invoving

• inertial frame of references A
• accelerating frame of references B
• both of these C
• none of these D

If the values of instantaneous and average velocities are equal, the body is said to be moving with

• uniform acceleration A
• uniform speed B
• variable velocity C
• uniform velocity D

The basic circuit element in A.C. circuits are:

• Resistor and capacitor A
• Resistor and Inductor B
• Capacitor only C
• Both (B) and (C) D
• None of these E

Newton's first law is also called:

• Law of torque A
• Law of force B
• Law of inertia C
• None of these D

The induced current in the loop can be increased by:

• Using a stronger magnetic field A
• Moving the loop faster B
• Replacing the loop by a coil of many turns C
• All above D
• Both (A) and (B) E

Certain light of wavelength 600 nm is used to view an object under the microscope. If the aperture of its objective is 1.22 cm, then the limiting angle of resolution will be:

• 6 x 10^-5rad A
• 7 x 10^-5rad B
• 8 x 10^-5rad C
• None of these D

Field lines are closer to each other in the region where the filed is

• Stronger A
• Weaker B
• Much weaker C
• Absent D
• None of these E

If time period of a pendulum is doubled by increasing its length, then its frequency will

• Also be doubled A
• Become half B
• Become one fourth C
• Becomes four times D